The present claimed invention relates to the field of flat panel displays. More particularly, the present claimed invention relates to interior structures of a flat panel display device.
Flat panel display devices often operate using electron emitting structures, such as, for example, Spindt-type field emitters. These types of flat panel displays typically employ a metallized polyimide structure to focus or define the path of electrons emitted from the electron emitting structures. In one prior art approach, the polyimide structure is referred to as a xe2x80x9cfocus waffle.xe2x80x9d The focus waffle is comprised of a xe2x80x9csheetxe2x80x9d or film-like structure having a plurality of openings formed therethrough. The focus waffle is disposed between the electron emitting structures and the faceplate such that emitted electrons pass through openings in the focus waffle structure, and are directed towards corresponding sub-pixel regions.
Additionally, the aforementioned sub-pixel regions on the faceplate of a flat panel display are typically separated by a polyimide-based opaque mesh-like structure commonly referred to as a black matrix. By separating sub-pixel regions, the polyimide black matrix prevents electrons directed at one sub-pixel from being xe2x80x9cback-scatteredxe2x80x9d and striking another sub-pixel. In so doing, the polyimide black matrix helps maintain a flat panel display with sharp resolution. In addition, the polyimide black matrix is also used as a base on which to locate structures such as, for example, support walls.
Unfortunately, due to the extremely high cost of certain types of polyimide material (especially photo-patternable polyimide material), such prior art polyimide-based black matrix and focus waffle structures are extremely expensive. As a result, a conventional polyimide black matrix and/or a polyimide focus waffle introduces substantial additional costs to flat panel display fabrication. As yet another disadvantage, such prior art polyimide focus waffle and black matrix structures are a major source of contamination in flat panel display devices. Typically, such contamination results from electron bombardment of the polyimide black matrix or focus waffle during normal operation of the flat panel display device. Hence, such xe2x80x9cdirtyxe2x80x9d polyimide focus waffle and polyimide black matrix structures introduce contaminate particles and/or desorbing gaseous species into the evacuated environment of the flat panel display device. These contaminate particles degrade the performance of the flat panel display device and reduce the effective lifetime of the flat panel display device via contamination of field emission surfaces and other possible mechanisms.
Thus, a need exists for a structure on the display cathode which effectively directs electrons emitted from electron emitters. A further need exists on the faceplate for a structure which effectively separates neighboring phosphor sub-pixels. A further need exists for a structure which meets the above-listed needs and which eliminates the use of expensive and contaminant producing polyimide material.
The present invention provides, in one embodiment, a structure on the display cathode which effectively directs electrons emitted from electron emitters. The present invention provides, in another embodiment, a structure on the faceplate which effectively separates neighboring phosphor sub-pixels. The present invention, in each of the above-mentioned embodiments, achieves the above-listed accomplishments without requiring the use of expensive and contaminant-producing polyimide material.
Specifically, in one embodiment, the present invention forms a molded structure over selected portions of a flat panel display device. Next, the present embodiment deposits an electroplating seed layer over the molded structure. After the deposition of the electroplating seed layer, the present embodiment electroplates material onto portions of the electroplating seed layer such that an electroplated structure is formed at desired regions of the flat panel display device. In such an embodiment, the present invention provides an electroplated structure which contains substantially no polyimide material. As a result, the present embodiment eliminates the cost and production of outgassed contaminants associated with prior art structures.
In another embodiment, the present invention includes the features of the above-described embodiment, and further recites that the electroplated structure is a black matrix structure of a flat panel display device.
In yet another embodiment, the present invention includes the features of the first above-described embodiment, and further recites that the electroplated structure is a focus waffle structure of a flat panel display device.
These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments which are illustrated in the various drawing figures.